An evaluation method for industrial organic solid waste pyrolysis based on the principle of entropy increase.

Abstract

This invention relates to the field of organic solid waste pyrolysis technology, and more particularly to an evaluation method for industrial organic solid waste pyrolysis based on the principle of entropy increase. The technical solution provided by this invention first calculates the total entropy value of the input substances in the pyrolysis system based on their entropy values; then, it calculates the total entropy value of the output substances based on their entropy values; next, it calculates the entropy change value generated by the pyrolysis system based on the total entropy values ​​of the input and output substances; finally, it calculates a comprehensive entropy efficiency index based on the entropy change value generated by the pyrolysis system, and uses this comprehensive entropy efficiency index to evaluate the pyrolysis system. Therefore, the above technical solution can analyze the entropy generated during the pyrolysis process, providing a theoretical basis for improving energy conversion efficiency and reducing negative environmental impacts in the pyrolysis process of industrial organic solid waste, and has guiding significance for achieving a sustainable development model for the utilization of industrial organic solid waste.

Description

Technical Field

[0001] This invention relates to the field of organic solid waste pyrolysis technology, and in particular to an evaluation method for industrial organic solid waste pyrolysis based on the principle of entropy increase. Background Technology

[0002] my country has a large output of industrial organic solid waste with high organic content, possessing significant resource potential. Meanwhile, pyrolysis technology, with its advantages of flexible operation, low cost, and high energy recovery efficiency, has become a rapid and efficient method for treating industrial organic solid waste.

[0003] However, existing research focuses more on the quantitative analysis of energy, while paying less attention to the quality differences in energy use and production processes.

[0004] Therefore, there is an urgent need for an evaluation method for the pyrolysis of industrial organic solid waste based on the principle of entropy increase to analyze the entropy generated during the pyrolysis process. Summary of the Invention

[0005] This invention provides an evaluation method for the pyrolysis of industrial organic solid waste based on the principle of entropy increase, which can analyze the entropy generated during the pyrolysis process.

[0006] This invention provides an evaluation method for the pyrolysis of industrial organic solid waste based on the principle of entropy increase, comprising:

[0007] The total entropy value of the input is calculated based on the entropy value of the input substances in the pyrolysis system; wherein, the input substances include industrial organic solid waste, diesel oil, air, water, and electricity; the pyrolysis system is used to pyrolyze the industrial organic solid waste;

[0008] The total entropy value of the output is calculated based on the entropy value of the output substances of the pyrolysis system; wherein, the output substances include biochar, bio-oil, waste gas, wastewater, ash, and heat entropy loss;

[0009] Calculate the entropy change value generated by the pyrolysis system based on the total entropy value of the input substance and the total entropy value of the output substance;

[0010] A comprehensive entropy efficiency index is calculated based on the entropy change value generated by the pyrolysis system, and the pyrolysis system is evaluated using the comprehensive entropy efficiency index.

[0011] As can be seen from the above scheme, the evaluation method for industrial organic solid waste pyrolysis based on the principle of entropy increase provided by the present invention first calculates the total entropy value of the input substances in the pyrolysis system, then calculates the total entropy value of the output substances in the pyrolysis system, then calculates the entropy change value generated by the pyrolysis system based on the total entropy values ​​of the input and output substances, and finally calculates the comprehensive entropy efficiency index based on the entropy change value generated by the pyrolysis system, so as to evaluate the pyrolysis system using the comprehensive entropy efficiency index. Therefore, the above technical solution can analyze the entropy generated in the pyrolysis process. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a schematic flowchart of an evaluation method for industrial organic solid waste pyrolysis based on the principle of entropy increase, provided in an embodiment of the present invention. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] Please see Figure 1 An embodiment of the present invention provides a schematic flowchart of an evaluation method for the pyrolysis of industrial organic solid waste based on the principle of entropy increase. The method includes:

[0016] Step 100: Calculate the total entropy value of the input substances based on their entropy values ​​in the pyrolysis system; wherein, the input substances include industrial organic solid waste, diesel oil, air, water, and electricity; the pyrolysis system is used to pyrolyze industrial organic solid waste.

[0017] Step 102: Calculate the total entropy value of the output based on the entropy value of the output substances of the pyrolysis system; wherein, the output substances include biochar, bio-oil, waste gas, wastewater, ash, and heat entropy loss;

[0018] Step 104: Calculate the entropy change value generated by the pyrolysis system based on the total entropy value of the input substance and the total entropy value of the output substance;

[0019] Step 106: Calculate the comprehensive entropy efficiency index based on the entropy change value generated by the pyrolysis system, so as to evaluate the pyrolysis system using the comprehensive entropy efficiency index.

[0020] In this embodiment, the total entropy value of the input substances is first calculated based on their entropy values. Then, the total entropy value of the output substances is calculated based on their entropy values. Next, the entropy change generated by the pyrolysis system is calculated based on both the total entropy values ​​of the input and output substances. Finally, a comprehensive entropy efficiency index is calculated based on the entropy change generated by the pyrolysis system, and this index is used to evaluate the pyrolysis system. Therefore, the above technical solution can analyze the entropy generated during the pyrolysis process.

[0021] In some implementations, the entropy generated during the pyrolysis of waste photovoltaic module EVA is calculated. The functional unit is set as 1 ton of EVA pyrolysis. First, the EVA raw material is dried by introducing EVA and N2 at 100°C under normal pressure. After drying, the hot N2 and dried EVA are separated and discharged. The dried EVA is then fed into a pyrolysis reactor and pyrolyzed at 500°C to obtain volatiles and ash. The volatiles are fully condensed to obtain pyrolysis oil and pyrolysis gas. The pyrolysis oil can be recycled, and the pyrolysis gas can be mixed with air for combustion, releasing heat to power the pyrolysis system. Finally, flue gas is discharged. Therefore, for the EVA pyrolysis process, the main inputs are EVA, N2, and air, and the main outputs are pyrolysis oil, waste flue gas, and ash. The entropy calculation data for 1 ton of EVA pyrolysis is shown in Table 1 (showing the input entropy, value, output entropy, value, and generated entropy).

[0022] Table 1. Entropy (MJ / K) generated by the conventional pyrolysis of EVA

[0023]

[0024] If solar energy is introduced to heat the EVA pyrolysis system and pyrolysis gas is output as a product, the entropy calculation results of 1 ton of EVA pyrolysis are shown in Table 2 (showing the input entropy, value, output entropy, value, and generated entropy).

[0025] Table 2 shows the entropy (MJ / K) generated by the partial substitution of solar energy for pyrolysis of EVA.

[0026]

[0027] Calculations show that the entropy generated during the conventional pyrolysis of EVA is positive, but becomes negative after the introduction of solar energy. This indicates that the EVA pyrolysis system becomes more ordered and efficient after the introduction of solar heating. This means that under these environmental conditions, the system's internal operation becomes more regular and coordinated, reducing waste and pollutant emissions and lowering the disorder output of the EVA pyrolysis system to the environment, thereby reducing output entropy. Furthermore, the reduction in output entropy also signifies an increase in energy conversion efficiency. In the solar pyrolysis scenario, pyrolysis gas is output as an effective energy product. Compared to the combustion and emission of flue gas in the traditional pyrolysis scenario, less energy is lost in a useless form, and more energy can be effectively converted into a useful form, directly improving energy conversion efficiency and reducing system disorder.

[0028] The data for various scenarios are shown below:

[0029] For the positive entropy production case: a1 = 0.2, b1 = 0.15, c1 = 0.1, d1 = 1.

[0030] For the case of negative entropy production: a2 = 0.1, b2 = 0.2, c2 = 0.05, d2 = 0.5.

[0031] Considering the absolute values ​​of both positive and negative entropy: a3 = 0.15, b3 = 0.1, c3 = 0.05, d3 = 0.5.

[0032] Weighting coefficients: ω1 = 0.3, ω2 = 0.5, ω3 = 0.2.

[0033] The CEEI calculation data for the EVA pyrolysis process are shown in Table 3 (showing the function name, conventional pyrolysis of EVA, and solar-alternative pyrolysis of EVA).

[0034] Table 3. CEEI Calculation Results for EVA Pyrolysis Process

[0035]

[0036] The results above show that the conventional pyrolysis system for EVA performs poorly, while the solar-powered partial pyrolysis system for EVA outperforms it. This system converts more input energy into usable output, improving overall efficiency and utilizing input energy more effectively, thus enhancing output quality. In practical applications, the CEEI value can be used to assess system performance, providing crucial reference for system optimization and decision-making.

[0037] Therefore, based on the above analysis, there are two main directions for optimizing the pyrolysis process: First, improve energy conversion efficiency, such as introducing renewable energy sources and efficiently separating and collecting pyrolysis products (solid, liquid, and gaseous) for rational utilization, thereby improving overall energy efficiency. Furthermore, recover the waste heat generated during pyrolysis for use in drying or preheating feed, reducing energy consumption. Second, reduce waste and pollutant emissions by utilizing clean energy sources such as solar and wind power to provide energy for the pyrolysis process, which can significantly reduce pollutants generated from fossil fuel combustion.

[0038] The analysis quantifies the quality and availability of energy in the pyrolysis system, as shown in Table 4 (which shows the name, typical pyrolysis components, etc.). (and solar pyrolysis components). By calculating different input and output energies The value can clearly define the effective energy available for doing work in the system.

[0039] Table 4 EVA pyrolysis process Analysis results

[0040]

[0041] The data table above provides a clear understanding of the input fuel. With the production of pyrolysis gas, bio-oil and other products This allows for the evaluation of the system's efficiency in energy quality conversion. It can also help identify energy loss points and amounts within the system. The analysis primarily focuses on the quality and availability of energy, but its explanation of the irreversible nature of energy conversion is not intuitive enough. The principle of entropy increase, from the perspective of the second law of thermodynamics, more profoundly explains why energy loss and unavailability always exist in actual processes, further illustrating the irreversibility of energy loss during use. For example, under certain complex pyrolysis conditions, relying solely on… Analysis may fall short of accurately explaining certain phenomena that appear to utilize energy efficiently but are actually inefficient. In such cases, the principle of entropy increase can reveal underlying irreversible processes and an increase in disorder, providing supplementary explanations. The fundamental cause of energy degradation not covered in the analysis, the principle of entropy increase provides a macroscopic perspective for assessing the overall thermodynamic performance of a system, and The analysis focuses more on the microscopic quality of energy and conversion efficiency. In summary, Analysis and the principle of entropy increase can complement each other in case studies, providing a comprehensive assessment from micro to macro levels. This allows for a more complete and in-depth evaluation of the system's energy utilization, providing stronger guidance for system optimization and improvement.

[0042] This method applies entropy analysis to the evaluation of industrial organic solid waste pyrolysis processes. It performs inventory analysis of the pyrolysis process, calculates the entropy generated at each functional unit during the pyrolysis stage, analyzes the entropy generated during pyrolysis, and identifies optimization directions for the pyrolysis process. This evaluation method can provide a theoretical basis for improving energy conversion efficiency and reducing negative environmental impacts in industrial organic solid waste pyrolysis processes, provide direction for further optimization of energy conservation and emission reduction efforts in this process, and offer a reference for evaluating the thermodynamic performance of industrial organic solid waste energy utilization. It also has guiding significance for achieving a sustainable development model for the utilization of industrial organic solid waste.

[0043] In one embodiment of the present invention, the entropy value of industrial organic solid waste is determined by the following formula:

[0044]

[0045] In the formula, m IOSW For the quality of industrial organic solid waste, HHV IOSW T represents the high calorific value of industrial organic solid waste, and T is the standard temperature.

[0046] In this embodiment, the system boundary of the industrial organic solid waste pyrolysis process is clearly defined. The starting boundary of this method is the collection of industrial organic solid waste, and the ending boundary is the acquisition of biochar and bio-oil products. The pyrolysis system covers stages such as transportation, pretreatment, pyrolysis, cooling, and heating. Its impact mainly includes electrical equipment such as crushers, dryers, and blowers, transportation vehicles, as well as energy and resource inputs and pollutant emissions due to biochar cooling and pyrolysis gas combustion.

[0047] The types of substances or energy at the input and output boundaries of each stage in the pyrolysis process of industrial organic solid waste are determined. At the same time, the input quantity list and temperature list of each substance or resource at each stage are determined, as well as the output quantity list and temperature list of each substance or energy at each stage.

[0048] In one embodiment of the present invention, the entropy value of diesel fuel is determined by the following formula:

[0049]

[0050] In one embodiment of the present invention, the entropy value of air is determined by the following formula:

[0051] S air =S airS ×m air

[0052] In the formula, S airS Let m be the specific entropy of air. air For air quality.

[0053] In one embodiment of the present invention, the entropy value of air is determined by the following formula:

[0054] S water =S waterS ×m water ;

[0055] In the formula, S waterS Let m be the specific entropy of water. water The quality of water.

[0056] In one embodiment of the present invention, the entropy value of electricity is determined by the following formula:

[0057]

[0058] In the formula, Q elec This refers to the amount of electricity input.

[0059] In one embodiment of the present invention, the total entropy value of the input is determined by the following formula:

[0060]

[0061] In the formula, S IOSW S is the entropy of industrial organic solid waste. dies S is the entropy of diesel fuel. air S is the entropy of air. water Let S be the entropy of the input water. elec The entropy of electricity.

[0062] In one embodiment of the present invention, the entropy value of biochar is determined by the following formula:

[0063]

[0064] In the formula, m biochar For the quality of biochar, HHV biochar Due to the high calorific value of biochar, T biochar The temperature at which biochar is formed.

[0065] In one embodiment of the present invention, the entropy value of the bio-oil is determined by the following formula:

[0066]

[0067] In the formula, m bio-oil For the quality of bio-oil, HHV bio-oil Due to the high calorific value of bio-oil, T bio-oil The temperature of the bio-oil.

[0068] In one embodiment of the present invention, the entropy value of the exhaust gas is determined by the following formula:

[0069]

[0070] In the formula, m i S is the mass of the gas. i Let be the specific entropy of the gas.

[0071] In one embodiment of the present invention, the entropy value of the wastewater is determined by the following formula:

[0072] S ww =m ww ×S wwS

[0073] In the formula, m ww For the quality of wastewater, S wwS is the specific entropy of the wastewater.

[0074] In one embodiment of the present invention, the entropy value of ash is determined by the following formula:

[0075]

[0076] In the formula, Q ash The heat of ash, T ash The temperature at which ash is separated, c ash m is the specific heat capacity of ash. ash Let denot be the mass of ash, and ΔT be the temperature difference.

[0077] In one embodiment of the present invention, the entropy value of the thermal entropy loss is determined by the following formula:

[0078] S loss =S IOSW ×3%.

[0079] In one embodiment of the present invention, the total entropy value of the output is determined by the following formula:

[0080]

[0081] In the formula, S biochar S is the entropy of biochar. bio-oil S is the entropy of bio-oil. exha S is the entropy of the exhaust gas. ww S is the entropy of the wastewater. ash Let S be the entropy of ash. loss This refers to the thermal entropy loss during the pyrolysis process.

[0082] In one embodiment of the present invention, the entropy change value generated by the pyrolysis system is determined by the following formula:

[0083]

[0084] In the formula, The total entropy value input to the pyrolysis system. The total entropy value output by the pyrolysis system. This represents the entropy change produced by the pyrolysis system.

[0085] In one embodiment of the present invention, the comprehensive entropy efficiency index is determined by the following formula:

[0086]

[0087] In the formula, ω1 is the first weighting coefficient, ω2 is the second weighting coefficient, and ω3 is the third weighting coefficient. For the first function, and for the second function, This is the third function.

[0088] In one embodiment of the present invention, the sum of the first weighting coefficient, the second weighting coefficient, and the third weighting coefficient is 1.

[0089] In one embodiment of the present invention, the first function is determined by the following formula:

[0090]

[0091] In the formula, when When, a1, b1, c1, and d1 are the first set of specific coefficients.

[0092] In one embodiment of the present invention, the second function is determined by the following formula:

[0093]

[0094] In the formula, when When, a2, b2, c2, and d2 are the second set of specific coefficients.

[0095] In one embodiment of the present invention, the third function is determined by the following formula:

[0096]

[0097] In the formula, a3, b3, c3, and d3 are the third set of specific coefficients.

[0098] In one embodiment of the present invention, the comprehensive entropy efficiency index is used to evaluate the pyrolysis system, including:

[0099] When the comprehensive entropy efficiency index is greater than the first preset value, the entropy production of the pyrolysis system is poor; where the first preset value is a positive number.

[0100] When the comprehensive entropy efficiency index is less than the first preset value and greater than the second preset value, the entropy production of the pyrolysis system is poor; where the second preset value is a positive number.

[0101] When the absolute value of the comprehensive entropy efficiency index is less than the second preset value, the entropy production of the pyrolysis system is better.

[0102] When the comprehensive entropy efficiency index is negative and its absolute value is greater than the third preset value, the entropy production of the pyrolysis system is good.

[0103] In this embodiment, the better the entropy production, the higher the energy efficiency of the system and the greater its contribution to sustainable development.

[0104] In some implementations, when the comprehensive entropy efficiency index is in a high positive range, it indicates that the negative impact of positive entropy production in the system is significant, the system performance is poor, and measures need to be taken to reduce positive entropy production.

[0105] When the comprehensive entropy efficiency index is in a low positive range, although the system produces positive entropy, the impact is relatively small and can be gradually optimized.

[0106] When the comprehensive entropy efficiency index is close to zero, the system is in a relatively balanced state, but there is still room for improvement.

[0107] When the comprehensive entropy efficiency index is in the negative range, it indicates that the system has a dominant negative entropy production and good system performance. The larger the negative value, the better the system performance.

[0108] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0109] It should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0110] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. An evaluation method for the pyrolysis of industrial organic solid waste based on the principle of entropy increase, characterized in that, The method includes: The total entropy value of the input is calculated based on the entropy value of the input substances in the pyrolysis system; wherein, the input substances include industrial organic solid waste, diesel oil, air, water, and electricity; the pyrolysis system is used to pyrolyze the industrial organic solid waste; The total entropy value of the output is calculated based on the entropy value of the output substances of the pyrolysis system; wherein, the output substances include biochar, bio-oil, waste gas, wastewater, ash, and heat entropy loss; Calculate the entropy change value generated by the pyrolysis system based on the total entropy value of the input substance and the total entropy value of the output substance; A comprehensive entropy efficiency index is calculated based on the entropy change value generated by the pyrolysis system, so as to evaluate the pyrolysis system using the comprehensive entropy efficiency index; The entropy value of the industrial organic solid waste is determined by the following formula: In the formula, m IOSW For the quality of industrial organic solid waste, HHV IOSW The high calorific value of industrial organic solid waste; T is the standard temperature. The entropy value of the diesel fuel is determined by the following formula: The entropy of the air is determined by the following formula: S air =S airS ×m air In the formula, S airS Let m be the specific entropy of air. air For air quality; The entropy value of the water is determined by the following formula: S water =S waterS ×m water ; In the formula, S waterS Let m be the specific entropy of water. water For the quality of water; The entropy of the electricity is determined by the following formula: In the formula, Q elec The amount of input electricity; The total entropy value of the input is determined by the following formula: In the formula, S IOSW S is the entropy of industrial organic solid waste. dies S is the entropy of diesel fuel. air S is the entropy of air. water Let S be the entropy of the input water. elec The entropy of electricity; The entropy value of the biochar is determined by the following formula: In the formula, m biochar For the quality of biochar, HHV biochar Due to the high calorific value of biochar, T biochar The temperature at which biochar is formed; The entropy value of the bio-oil is determined by the following formula: In the formula, m bio-oil For the quality of bio-oil, HHV bio-oil Due to the high calorific value of bio-oil, T bio-oil The temperature of the bio-oil; The entropy value of the exhaust gas is determined by the following formula: In the formula, m i S is the mass of the gas. i is the specific entropy of the gas; The entropy value of the wastewater is determined by the following formula: S ww =m ww ×S wwS In the formula, m ww For the quality of wastewater, S wwS Specific entropy of wastewater; The entropy value of the ash is determined by the following formula: In the formula, Q ash The heat of ash, T ash The temperature at which ash is separated, c ash m is the specific heat capacity of ash. ash The mass of ash is ΔT, and the temperature difference is ΔT. The entropy value of the heat entropy loss is determined by the following formula: S loss =S IOSW ×3%; The total entropy value of the output is determined by the following formula: In the formula, S biochar S is the entropy of biochar. bio-oil S is the entropy of bio-oil. exha S is the entropy of the exhaust gas. ww S is the entropy of the wastewater. ash Let S be the entropy of ash. loss This refers to the heat entropy loss during the pyrolysis process; The entropy change value generated by the pyrolysis system is determined by the following formula: In the formula, The total entropy value input to the pyrolysis system. The total entropy value output by the pyrolysis system. This represents the entropy change produced by the pyrolysis system. The comprehensive entropy efficiency index is determined by the following formula: In the formula, ω1 is the first weighting coefficient, ω2 is the second weighting coefficient, and ω3 is the third weighting coefficient. For the first function, For the second function, It is the third function; The first function is determined by the following formula: In the formula, when At that time, a1, b1, c1, and d1 are the first set of specific coefficients; The second function is determined by the following formula: In the formula, when At that time, a2, b2, c2, and d2 are the second set of specific coefficients; The third function is determined by the following formula: In the formula, a3, b3, c3, and d3 are the third set of specific coefficients.

2. The method according to claim 1, characterized in that, The sum of the first weighting coefficient, the second weighting coefficient, and the third weighting coefficient is 1.

3. The method according to claim 1, characterized in that, The evaluation of the pyrolysis system using the comprehensive entropy efficiency index includes: When the comprehensive entropy efficiency index is greater than the first preset value, the entropy production of the pyrolysis system is poor; wherein, the first preset value is a positive number. When the comprehensive entropy efficiency index is less than the first preset value and greater than the second preset value, the entropy production of the pyrolysis system is poor; wherein, the second preset value is a positive number. When the absolute value of the comprehensive entropy efficiency index is less than the second preset value, the entropy production of the pyrolysis system is better. When the comprehensive entropy efficiency index is negative and its absolute value is greater than the third preset value, the entropy production of the pyrolysis system is good.

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